PM10 emissions and PAHs: The importance of biomass type and combustion conditions

The aim of the present work was to investigate the impact of biomass combustion with respect to conditions and fuel types on particle emissions (PM10) and their PAHs content. Special concern was on sampling, quantification and characterization of PM using different appliances, fuels and operating procedures. For this purpose different lab-scale burning conditions, two pellets stoves (8.5 and 10 kW) and one open fireplace were tested by using eight fuel types of biomass. An analytical method is described for the quantitative determination of 16 PAHs using liquid-liquid extraction and subsequent measurement by gas chromatography coupled to a mass spectrometer (GC-MS). Average PM10 emissions ranged from about 65 to 170 mg/m(3) at lab-scale combustions with flow oxygen at 13% in the exhaust gas, 85-220 mg/m(3) at 20% O-2, 47-83 mg/m(3) at pellet stove of 10 kW, 34-69 mg/m(3) at pellet stove of 8.5 kW and 106-194 mg/m(3) at the open fireplace. The maximum permitted particle emission limit is 150 mg/m(3). Pellets originated from olive trees and from nonmixture trees were found to emit the lowest particulate matter in relation to the others, so they are considered healthiest and suitable for domestic heating reasons. In general, the results show that biomass open burning is an important PM10 and PAHs emission source.